Page:Travels in Mexico and life among the Mexicans.djvu/188

180 residence of Dr. Trowbridge here as our Consul, during which he has discharged the duties of the office faithfully, and won respect from every body, should entitle him to a reappointment. It is impossible for one not acclimated to reside in this city long without receiving a visit from the vomito, which may prove fatal. The Doctor and his family have passed through many bad seasons, they have all had the fever, and it is to be hoped they may be spared yet many years to live in a place they seem to like."

Though Vera-Cruzians deny that the vomito is endemic here, it has existed too long in this place to have their assertion believed. The oldest description of yellow fever is that of a Portuguese physician, who observed it in Brazil, between 1687 and 1694; and its first appearance in Mexico is said by the historian Clavigero to have been in 1725. Even the best of our physicians disagree as to the origin, and even the contagious character, of the vomito; hence, we will not discuss this vexed question. But it would seem that the latest theory, that of a South American physician, that it is propagated by germs from the soil in which fever victims have been buried, and thus rendered endemic, was more nearly correct than any other yet advanced. It has been noted that it rages more violently in some seasons than in others; and Humboldt stated that an intimate connection was always observed between the march of diseases and the variations of atmospheric temperature. "Two seasons only are known at Vera Cruz,—that of the north winds (los nortes), from the autumnal to the vernal equinox, and that of the south winds, or breezes (brisas), between March and September, The month of January is the coldest in the year, because it is farthest from the two periods in which the sun passes through the zenith of Vera Cruz (the 16th of May and the 27th of July). The vomito generally begins to rage in that term when the mean temperature of the month reaches 75° Fahrenheit. In December, January, and February, the heat remains below this limit; and, accordingly, it seldom happens that the yellow fever does not entirely disappear in that season, when a very sensible cold is frequently felt."

The last and the first months of the year, then, are the safest